Metapontum was an important city of Magna Graecia, situated on the gulf of Tarentum, between the river Bradanus and the Casuentus (modern Basento). It was founded by the Achaeans of the Greek Peloponnese c. 720 BCE as part of the wave of Greek colonization from the 8th century BCE onwards across the entire region of southern Italy. Thriving on agriculture and trade, the city became one of the most prosperous colonies in Magna Graecia.
Today, the best surviving evidence of Metapontum's importance in antiquity is the 6th century BCE Temple of Hera with 15 of its Doric columns still standing. A theatre was built over the assembly place in the 5th century BCE which had half columns and a Doric frieze. The theatre was remodelled again in the mid-4th century BCE and in its current form measured 62 metres at its widest part and could seat some 8,000 people.
References:The ancient Argos Theater was built in 320 BC. and is located in Argos, Greece against Larissa Hill. Nearby from this site is Agora, Roman Odeon, and the Baths of Argos. The theater is one of the largest architectural developments in Greece and was renovated in ca 120 AD.
The Hellenistic theater at Argos is cut into the hillside of the Larisa, with 90 steps up a steep incline, forming a narrow rectilinear cavea. Among the largest theaters in Greece, it held about 20,000 spectators and is divided by two landings into three horizontal sections. Staircases further divide the cavea into four cunei, corresponding to the tribes of Argos A high wall was erected to prevent unauthorized access into the theatron and may have helped the acoustics, but it is said the sound quality is still very good today.
Around 120 CE, both theaters were renovated in the Roman style.